Unit of Technology of Fuels, RWTH Aachen University, Aachen, Germany.
Professor of Process and Chemical Reaction Engineering, Department of Engineering and Natural Sciences, University of Applied Sciences Merseburg, Merseburg, Germany.
Waste Manag Res. 2022 Oct;40(10):1494-1504. doi: 10.1177/0734242X221084044. Epub 2022 Mar 15.
Increased media coverage of plastic pollution in the environment and import bans on plastic waste in several countries have resulted in plastic waste becoming one of the most discussed waste streams in recent years. In the European Union (EU), only about one-third of the post-consumer plastic waste is recycled; the rest goes to energy recovery and landfilling in equal parts. In connection to the necessary increase in efforts to achieve the ambitious EU recycling targets, chemical recycling is currently receiving more and more attention. The assumption is that chemical recycling processes could open up new waste streams for recycling and generate valuable raw materials for the chemical industry. Although there exists no legal definition for chemical recycling, there is more or less agreement that it covers the conversion of plastic polymers into their monomers or chemical building blocks. Techniques such as gasification, pyrolysis and liquefaction as well as solvolysis can be used for chemical recycling. So far, only few large-scale plants for chemical recycling exist worldwide. This article presents the different processes by means of examples from (formerly) running installations and their suitability for plastics recycling is assessed. However, to date, only few chemical recycling plants are in continuous operation, and further scientific evidence for the ecological and economic benefits is still necessary for final evaluation.
媒体对环境中塑料污染的报道增加，以及几个国家对塑料废物的进口禁令，导致塑料废物成为近年来讨论最多的废物之一。在欧盟（EU），只有约三分之一的消费后塑料废物被回收；其余的则等量用于能源回收和填埋。为了实现雄心勃勃的欧盟回收目标，有必要加大努力，因此化学回收目前受到越来越多的关注。人们假设化学回收工艺可以为回收开辟新的废物流，并为化学工业生成有价值的原材料。虽然化学回收没有法律定义，但人们或多或少都认为它包括将塑料聚合物转化为其单体或化学结构单元。化学回收可采用气化、热解和液化以及溶剂解等技术。迄今为止，全世界只有少数几个大型化学回收工厂。本文通过（以前）运行的装置实例介绍了不同的工艺，并评估了它们对塑料回收的适用性。然而，到目前为止，只有少数几家化学回收工厂在连续运行，为了最终评估，还需要进一步的科学证据来证明其在生态和经济方面的效益。
